Electric Heated Drop Bottom Furnaces AMS 2750E specifications
Electric heated drop bottom furnaces are more economic to manufacture but create higher energy cost then fuel gas fired furnaces. The load is heated by convection. Metallic heating elements in the form of coiled resistance wire (aka wire wound heating elements) are exposed to an air stream generated by a fan. The heat is transferred from the heating element into the air stream and then into the part. The life expectancy of the heating elements is long due the relative low process temperatures for metallic heating elements. If heating specification call for shielding from direct heat radiation, then a downdraft design with radiation shields can be chosen or the heating element can be installed into the ducts.
Electric heated bottom drop industrial furnaces for solution heat treatment of aluminum and magnesium alloys are used when products of combustion in the air stream are not tolerable, energy cost are not a main concern and investment cost for indirect gas fired equipment are not justifiable.